docker-compose.yml

version: '3.8'  # Docker Compose file format version

services:  # "services" = containers we want to run

  # Service 1: MongoDB
  mongodb:
    image: mongo:7.0  # Download official MongoDB 7.0 from Docker Hub
    container_name: video-app-mongodb  # Give it a friendly name
    restart: unless-stopped  # Auto-restart if it crashes
    ports:
      - "27017:27017"  # Expose port: YOUR_COMPUTER:CONTAINER
                       # Makes MongoDB accessible at localhost:27017
    environment:
      MONGO_INITDB_DATABASE: video_app  # Create database named "video_app"
    volumes:
      - mongodb_data:/data/db  # Save data to persistent volume
                               # (data survives container restarts)
    networks:
      - video-app-network  # Put on custom network
    healthcheck:  # Check if MongoDB is ready
      test: echo 'db.runCommand("ping").ok' | mongosh localhost:27017/video_app --quiet
      interval: 10s  # Check every 10 seconds
      timeout: 5s
      retries: 5

  # Service 2: Flask Backend
  backend:
    build:
      context: ./  # Build from current directory
      dockerfile: Dockerfile  # Use our Dockerfile
    container_name: video-app-backend
    restart: unless-stopped
    ports:
      - "5000:5000"  # Expose Flask on port 5000
    environment:
      # Environment variables for the backend
      - MONGODB_URI=mongodb://mongodb:27017/video_app
        # "mongodb" here refers to the service name above
        # Docker DNS resolves "mongodb" to the container's IP
      - JWT_SECRET_KEY=your_secret_key
      - FLASK_ENV=production
    depends_on:
      mongodb:
        condition: service_healthy  # Wait for MongoDB to be ready
    networks:
      - video-app-network  # Same network as MongoDB
    command: sh -c "python seed_videos.py && python app.py"
             # First seed the database, then start Flask

volumes:
  mongodb_data:  # Named volume for MongoDB data persistence
    driver: local  # Store on local disk

networks:
  video-app-network:  # Custom network for service communication
    driver: bridge